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#include "src/tint/lang/core/ir/transform/add_empty_entry_point.h"

#include <utility>

#include "src/tint/lang/core/ir/builder.h"
#include "src/tint/lang/core/ir/constant.h"
#include "src/tint/lang/core/ir/module.h"
#include "src/tint/lang/core/ir/validator.h"

using namespace tint::core::number_suffixes;  // NOLINT

namespace tint::core::ir::transform {

namespace {

void Run(ir::Module& ir) {
    for (auto& func : ir.functions) {
        if (func->IsEntryPoint()) {
            return;
        }
    }

    ir::Builder builder{ir};
    auto* ep = builder.ComputeFunction("unused_entry_point");
    ep->Block()->Append(builder.Return(ep));
}

}  // namespace

Result<SuccessType> AddEmptyEntryPoint(Module& ir) {
    auto result =
        ValidateAndDumpIfNeeded(ir, "core.AddEmptyEntryPoint", kAddEmptyEntryPointCapabilities);
    if (result != Success) {
        return result.Failure();
    }

    Run(ir);

    return Success;
}

}  // namespace tint::core::ir::transform
